Supplemental pendulum-bob



(No Model.)

H. S. PRENTISS. SUPPLEMENTAL PENDULUM BOB.

Patented Apr. 14,1891.

Rq/l.

INVENTUR: Ken 5" Prencuss m ATTORNEY UNITED STATES PATENT OFFICE.

HENRY S. PRENTISS, OF ELIZABETH, NEIV JERSEY.

SUPPLEMENTAL PENDULUM-BOB.

SPECIFICATION forming part of Letters Patent'No. 450,529, dated April 14, 1891.

Application filed November 10, 1890. Serial No. 370,882. (No model.)

My invention has reference to improve ments in clock-pendulums, and especially to the supplemental or rating bobs usually provided in connection with the main bob for facilitating the adjustment of the pendulum for time. lleretofore ordinary nuts in en gagement with the screw-shank of the pendulum have been used for this purpose; but such nuts, necessarily being fitted loosely to the screw-shank, so as to turn without twisting the pendulum and not having the weight of the main bob to support, are influenced by the oscillation of the pendulum and caused to work downward, thereby throwing the pendulum out of adjustment.

My invention has, therefore, for its object to provide a supplementary or rating bob which can be easily turned for adjustment and will not be influenced by the motion of the pendulum, even after the thread has become worn.

To this end my invention consists, essentially, in combining with a pendulum a supplementary or rating bob composed of a split sleeve having its upper portion reduced and provided with an internal screw-thread, all of which is more fully pointed out in the following specification and claims and illustrated in the accompanying drawings, in Which- Figure 1 represents a face view of a pendulum embodying my invention, part being broken away. Fig. 2 is a sectional side elevation of the same. Fig. 3 is a sectional elevation of the supplementary or rating bob detached. Fig. 4c is a section through the line X X, Fig. 3.

Similar letters indicate corresponding parts.

In the drawings, the letter A designates the rod of the pendulum.

B is the main bob, and G the adjusting-nut supporting the former and engaging with the serew-shank I), secured to the lower end of the red A, all as usual. The supplementary or rating bob E is made of metal and formed with the nutted head or weight proper to and a cylindrical portion or sleeve Z), split through a major portion of its length. The upper end of the sleeve is reduced in diameter and provided with an internal screw-thread 0,0011- structed to engage with the screw-shank D of the pendulum, the whole acting in the manner of internally-threaded spring-jaws, the upper threaded portions of which engage with said screw-shank. The upper end of the rating-bob is reduced sufficiently in diameter to fit snugly about the screw-shank D, the split sleeve then exerting sufficient pressure at all times to prevent the bob from turning with the oscillations of the pendulum, while at the same time the pressure is not such as to cause the pendulum to be twisted when the bob is adjusted by hand. Furthermore, as the screwthreads wear the elasticity of the sleeve will take up for wear.

What I claim as new, and desire to secure by Letters Patent, is-

1. In combination with a pendulum, a supplemental or rating bob provided with a split sleeve and internal serew-th reads, substantially as described.

2. A pendulum-bob having a split sleeve reduced in diameter at its upper end and provided with an internal screw-thread, substantially as described.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 5th dayof November, 1890.

HENRY S. PRENTISS.

Witnesses:

A. FABER DU FAUR, J12, ALBERT B. Braemvoon. 

